JPH05196363A - Seal device for rotary kiln - Google Patents

Abstract

PURPOSE:To provide a seal device for a rotary kiln which can be used through the flow of explosive gas through the furnace core pipe of the rotary kiln. CONSTITUTION:A sealing device for a rotary kiln is formed such that a surrounder 2 with which the end part of a furnace core pipe 1 is surrounded and the interior of which is communicated to the furnace core pipe is provided and a gap between the surrounder and the furnace core pipe rotated based on the surrounder is held in an airtight state. In the sealing device, a flange-form part 17 loosely engaged with the outer periphery of the furnace core pipe is provided. A first seal part 14 is arranged between an inner hole 16 of a flange- form part and the outer peripheral surface of the furnace core pipe such that axial displacement of the furnace core pipe from the flange-form part is allowed and axial inclination of the furnace core based on the flange-form part is allowed. A second seal part 15 is arranged between the two surfaces of the flange- form part and the part of the surrounder, in a manner to be positioned facing the two surfaces throughout a whole periphery, so that eccentric rotation of the flange-form part based on the surrounder is allowed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary kiln sealing device which is applied for airtightly partitioning a furnace core tube of a rotary kiln with the outside.

[0002]

2. Description of the Related Art Conventionally, an oil seal is often used as a seal between a general rotary shaft and a penetrating portion thereof. In that case, the shaft is made of metal and the outer peripheral surface is favorably machined, that is, the outer peripheral surface is smooth, the roundness is high, the distortion is small, and the eccentric rotation is hard to occur.

In the case of the furnace core tube of the rotary kiln, metal or ceramic is used, but since the furnace core tube is heated, thermal distortion is caused by irregular expansion in the axial direction and the diametrical direction, and this is rotated. When it is done, it rotates eccentrically. When the furnace core tube is made of ceramic, the condition of the outer peripheral surface is not as good as when it is made of metal, and the roundness is not so good. Therefore, it was almost impossible to make an airtight seal in the furnace core tube with a normal oil seal. For this reason, it was impossible to use a rotary kiln for circulating an explosive gas in the furnace core tube of the rotary kiln.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a rotary kiln sealing device which can be used to circulate an explosive gas in a furnace core tube of a rotary kiln.

[0005]

The rotary kiln sealing device according to the present invention is provided with an envelope that surrounds the end of the furnace core tube and communicates with the inside of the furnace core tube. In a rotary kiln sealing device that maintains airtightness between a furnace core tube that rotates with respect to an envelope, a flange-shaped portion that is loosely fitted to the outer periphery of the furnace core tube is provided, and the collar-shaped portion inner hole and the furnace core are provided. A first seal portion is provided between the outer peripheral surface of the tube and the outer peripheral surface of the tube so as to allow axial displacement of the furnace core tube with respect to the collar portion and allow inclination of the axis of the furnace core tube with respect to the collar portion. A second seal for allowing eccentric rotation of the collar-shaped portion with respect to the envelope between both sides of the collar-shaped portion and a portion of the envelope provided on both sides so as to face each other around the entire circumference. It is characterized in that a section is provided.

[0006]

[Function] The furnace core tube is distorted by heating, but the distortion is caused at the end of the furnace core tube where the seal is provided.
It appears as the axial displacement of the furnace core tube, the displacement in the direction perpendicular to the axial line, and the inclination of the axial line. The axial displacement of the furnace core tube is
Allowed by the first seal. That is, even if the furnace core tube moves in the axial direction, the movement is allowed, and the first seal portion is in a substantially fixed position. The axial displacement is stable and does not fluctuate much when the core tube reaches a predetermined operating temperature. However, the displacement in the direction perpendicular to the axis and the inclination of the axis cause the eccentric rotation and the eccentric rotation of the core tube even if the core tube reaches a predetermined operating temperature and the strain becomes stable. Appears as whirling. Therefore, the collar portion tends to eccentrically rotate and whirl with the furnace core tube. On the other hand, since the collar-shaped portion is restrained by the portion of the envelope via the second seal portion, the furnace core tube is inclined with respect to the collar-shaped portion, but this inclination is caused by the first seal portion. Tolerated by As a result, the collar-shaped portion is merely eccentrically rotated, and this eccentric rotation is allowed by the second seal portion. That is,
The eccentric rotation and whirling of the furnace core tube are allowed by the first and second seal portions. By thus providing the seal portion separately for the first and second seal portions, it is possible to absorb all the influence on the seal portion due to the thermal strain of the furnace core tube. Therefore, the first and second seal portions can be absorbed.
The seal portions can maintain their respective sealing action.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. This example is a laboratory rotary kiln ceramic core tube sealing device. In the figure, 1
Is a furnace core tube, 2 is an envelope, 3 is a sealing device, 4 is a base frame, and the figure shows the peripheral portion of the end portion of the furnace core tube 1 on the workpiece supply side.

The furnace core tube 1 has an outer shape of 60 mm, a longitudinal middle portion is located in the furnace 10, both ends penetrate the furnace wall 11 and go out of the furnace, and a part that goes out of the furnace. Fin for cooling 1
2 is provided, the outer peripheral surface of which is supported by the roller 13 and further terminates at the outer side thereof, and the end portion is surrounded by the envelope 2 so that both insides communicate with each other. A sealing device 3 is provided between the end of the tube 1 and the envelope 2.

The seal device 3 includes a first seal portion 14 and a second seal portion.
The seal portion 15 is included. The first seal portion 14 is the core tube 1
Is provided with a metallic collar-shaped portion 17 having an inner hole 16 that is loosely fitted to the outer periphery of the end of the furnace, and the first sealing material is provided between the inner hole 16 of the collar-shaped portion 17 and the outer peripheral surface of the end of the furnace core tube 1. An O ring is provided as 18.

The second seal portion 15 surrounds the outer peripheral edge of the collar-shaped portion 17 with a space between the envelope 2 and the second seal portion 15.
The annular groove 19 is provided on the inner surface of the annular groove 19, and the second sealing material 21 is provided between both side walls 20 of the annular groove 19 and both surfaces of the flange portion 17. The second seal member 21 is formed of an elastic body for rubber in an annular shape with a uniform cross section, is fixedly provided on both side walls 20 of the annular groove 19, and has a small roundness at the tip from the side wall 20 side as shown in the drawing. It projects in a triangular shape, and its tip portion abuts on both sides of the collar portion 17. Metal collar 1
Both sides of 7 are machined into smooth flat surfaces.

The envelope 2 is in the shape of an airtight container and has a gas passage 22 connected to the upper end thereof, and a supply pipe connecting portion in which an object supply pipe 23 is airtightly penetrated to an end extended position of the furnace core tube 1. 24 is provided. An outer end of the supply pipe 24 is connected to a supply device 25 for supplying an object to be treated (for example, powder, granules, etc.), and an inner end thereof extends and terminates in the furnace core tube 1.

The above-mentioned furnace 10, roller 13, envelope 2,
The object supply device 25 and the like are supported by the base frame 4, and the right side of the drawing is slightly raised as a whole. Furnace core tube 1
Although not shown in the drawing, the left end of the inside of the envelope is in an envelope similar to the envelope 2 and the same sealing device as above is provided in the penetrating portion of the envelope wall to provide a roller for receiving a thrust load. Is provided in the envelope. A gas passage is connected to the upper part of the envelope, and a delivery part for delivering the processed product is provided in the lower part. The furnace core tube 1 between the envelope and the furnace 10 is provided with the cooling fins and rollers similar to those described above, and the roller is provided with a rotation driving unit so that each furnace core tube 1 is provided. It is designed to rotate at a speed of 15 times per minute.

When the rotary kiln is started by raising the right side of the base frame 4, the furnace core tube 1 expands by heating and expands in the axial direction. Therefore, it appears as a large axial displacement at the right end of the figure. This axial displacement allows the outer periphery of the furnace core tube 1 to slide in the axial direction with respect to the inner periphery of the first sealing material 18. When the furnace core tube 1 is rotated, the flange portion 17 rotates together with the furnace core tube 1. This can be achieved by making the contact pressure of the first sealing material 18 with respect to the furnace core tube 1 and the flange portion 17 sufficiently larger than the contact pressure of the second sealing material.

The furnace core tube 1 bends due to thermal strain or weight, and the end of the furnace core tube 1 swings around at the sealing device 3. In a state where the end of the furnace core tube 1 whirls around, the collar-shaped portion 17 tries to whirl together, but the collar-shaped portion 17
Is restrained by the second seal material 21, the furnace core tube 1 tilts with respect to the flange portion 17, and this tilt is reasonably allowed by the slight deformation of the first seal material 18,
The collar portion 17 is a simple eccentric rotation in which the flange portion 17 is eccentrically rotated along substantially the same plane. The eccentric rotation of the collar-shaped portion 17 is naturally allowed by sliding with the second sealing material.
Therefore, the first seal portion 14 and the second seal portion 15 both allow the rotation of the furnace core tube without impairing the sealing function.

When the object to be treated is supplied from the supply device 25 in this state, the object to be treated is gradually fed by the rotation of the inclined furnace core tube 1 and heat-treated during the period to reach the feeding section. In this heat treatment, when an explosive gas, harmful gas, etc. are applied, or when harmful gas is generated,
Gas is supplied or discharged using the gas passage 22. According to the configuration of this example, the eccentricity of the furnace core tube 1 was within 3 mm in the radial direction, and the gas pressure inside could withstand up to about 100 mm in the water column.

Although the O-ring is used as the first seal material 18 in the above-described embodiment, other first seal materials 18a, 18b having a sectional shape as shown in FIG. 3 can be used.

[0017]

According to the present invention, even if the furnace core tube of the rotary kiln is made of a ceramic whose surface strip is not so good, it is possible to provide a sealing device capable of maintaining airtightness by contacting with the outer peripheral surface thereof. In addition, it is possible to use a rotary kiln that allows an explosive gas to flow in a furnace core tube, which has been almost impossible in the past.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view of a main part of an embodiment of the present invention.

FIG. 2 is a partial cross-sectional front view showing a configuration of a furnace core tube peripheral portion of the rotary kiln of the embodiment.

3 (a) and 3 (b) are cross-sectional views showing cross-sectional shapes of other first sealing materials in the present invention.

[Explanation of symbols]

 1 Furnace Core Tube 2 Envelope 3 Sealing Device 14 First Sealing Part 15 Second Sealing Part 16 Inner Hole of Collar-shaped Part 17 Collar-shaped Part 18 First Sealing Material 19 Annular Groove 21 Second Sealing Material

Claims (1)

[Claims] 1. An envelope is provided which surrounds an end portion of the furnace core tube and communicates with the inside of the furnace core tube, and between the envelope and the furnace core tube rotating with respect to the envelope. In a rotary kiln sealing device that holds airtightly, a collar-shaped portion that is loosely fitted to the outer periphery of the furnace core tube is provided, and the furnace for the collar-shaped portion is provided between the inner hole of the collar-shaped portion and the outer peripheral surface of the furnace core tube. A first seal portion is provided to allow the axial displacement of the core tube and to allow the axial line of the furnace core tube to tilt with respect to the collar portion, and to cover both surfaces of the collar portion and the entire circumference thereof. A sealing device for a rotary kiln, wherein a second seal portion is provided between the portion of the envelope provided so as to face each other and the eccentric rotation of the collar portion with respect to the envelope. ..